It has recently been shown that a new class of optical solitons occur in dispersion managed systems where alternating sections of negative (anomalous) and positive (normal) dispersion fibre are used. (See, for example, Suzuki, M., Morita, I., Edagawa, N., Yamamoto, S., Taga, H., and Akiba, S., `Reduction of Gordon-Haus timing jitter by periodic dispersion compensation in soliton transmission`, Electron. Lett., 1995, 31, (23), pp. 2027-2029, Smith, N. J., Knox, F. M., Doran, N. J., Blow, K. J., and Bennion, I., `Enhanced power solitons in optical fibres with periodic dispersion management`, Electron. Lett., 1996, 32, (1), pp54-55 and Smith, N. J., Forysiak, W., and Doran, N. J., `Reduced Gordon-Haus jitter due to enhanced power solitons in strongly dispersion managed systems`, Electron. Lett., 1996, 32, (22), pp2085-2086.
In a further paper entitled `Energy scaling characteristics of solitons in strongly dispersion-managed fibres`, Opt. Lett., 1996. 21, (24), pp1981-1983, Smith et al. derived an empirical relationship for the enhanced power of these solitons, where the average dispersion is anomalous and significantly less (in magnitude) than the dispersion in the two segments. These lossless calculations showed the importance of the launch point in the map (the minimum chirp is at the centre of either section), but did not establish the exact pulse shape, nor the long term stability of the pulses.